When the _raw sugar_, as it is called, reaches the refinery, which is generally a tall building, it is taken to the top story and dissolved in hot water. It then passes through bags which act as _filters_, and through a great cylinder which contains burned bones, known as _bone-black_. You remember that I told you that the bones of the cattle were saved. This is one of the uses to which they are put. When the liquid comes out of this bone filter it is a perfectly clear sirup, which is then crystallized. [Illustration: FIG. 27.--A Sugar Mill.] You know that we buy refined sugar in three forms: granulated sugar, loaf sugar, and pulverized sugar. When granulated sugar is wanted, the crystals are placed in a great drum, which revolves until they are thoroughly dried in the right form. To make loaf sugar, the crystals are pressed into molds, then dried, and cut into the size desired. In powdered sugar they are simply ground to a powdered condition. Think how much labor is required to produce sugar, and yet you can buy it for five cents a pound. There are great fields of sugar cane in the Gulf states, in Cuba, in the Hawaiian Islands, in the East Indies, in India, and in other warm, moist parts of the world. We buy a great deal of sugar from Cuba, and from the Hawaiian Islands. To what city do you think the sugar from the Hawaiian Islands is sent? BEET SUGAR Although the cane fields of the moist, hot countries yield great quantities of sugar, there are other sources from which this useful product comes. In the year 1747 a German scientist discovered that sugar can be made from beets, and now about two thirds of our supply come from these plants. The sugar beet is not just like the plant of the same name which we raise for table use. It is white, and sometimes weighs as much as ten or fifteen pounds. Beets do not need so much water nor so much heat as sugar cane, so they can be raised in Germany, France, Austria, Russia, and other countries, as well as in California, Utah, and Nebraska, in our own land. In some parts of California there are fields of beets stretching for miles. The seeds are planted in rows, which, after the plants have come up, are thinned. In four or five months from the time the seeds are planted, the beets are ready to harvest. On most of the large _ranches_ the beets are dug by machinery. Men then move back and forth in the fields, cutting off the leaves and a little of the upper part of the beet, for this contains too much mineral matter to be of value in making sugar. The workmen use large knives, and they walk on their knees.